ive bought the game yesterday, and i really like it, except somemajor issue for me:If you upgrade your mage tower/guild etc. new monsters types get unlocked, and they startto appear everywhere in dungeons (and thus making even the easy starting dungeons from thebeginning much harder). Why does the game gets harder if i upgrading things?Is there a way to disabling the new monster type?

The game's getting harder because you're getting access to more tools to beat it with That's the design philosophy that's behind all of DD: You're getting better as a player, so we're challenging you more. Hope that's not too discouraging!